Current virtual reality (VR) and augmented reality (AR) often use visual tracking of large-body movements. Visual tracking uses optical or infrared cameras to track major body motions to control a user's VR or AR environment. These cameras, however, suffer from inadequate spatial resolution and sensitivity to light and darkness.
Some VR and AR systems use hand-held controllers. These controllers, however, do not permit the great breadth of control that is often desired to control a VR/AR world, as they are limited by the number and orientation of buttons or inadequate motion-sensing sensors, such as accelerometers. Further, hand-held controllers often are nearly worthless for VR, as in VR it is desirable to know a user's body and hand orientation within the VR world, which hand-held controllers do not provide.
A partial solution to this problem involves radio-frequency (RF) techniques that track a point on a moving object. These current RF techniques, however, struggle to determine small motions without having large, complex, or expensive radar systems due to the resolution of the radar tracking system being constrained by the hardware of the radar system.